docs: def record_leaving(self, time, code, frame_key, parent_stats):
          """Left from a function call."""
          try:
              stats = parent_stats.get_child(code)
              time_entered = self._times_entered.pop((code, frame_key))
          except KeyError:
              return
          time_elapsed = time - time_entered
          stats.deep_time += max(0, time_elapsed)